After negotiating a fresh deal with Rishi Sunak for Northern Ireland after Brexit, King talks with Ursula von der Leyen at Windsor Castle.
Sources from The palace says the King won't negotiate, won't be political, and won't forget his constitutional duties.
The Government advised the duo to meet to address climate change, Ukraine, and other concerns.
Because of his busy schedule, His Majesty won't have any more in-person meetings, and their meeting will coincide with other events.
Sources say that the Prime Minister will always keep the King up to date on all government and state business.
The palace verified "backup preparations" for the King to visit Mrs. von der Leyen at Windsor Castle on Saturday if the accord wasn't finalised on time.
The meeting could engage the King in a sensitive political issue, according to Democratic Unionist Party leader Sammy Wilson.
Former Northern Ireland first minister Arlene Foster stated that she didn't like No10 asking HM the King to help with a contentious deal.
The Monarch should only be involved after things are finished and accepted, according to Tory Brexiteer Jacob Rees-Mogg.